Make XLogRecGetBlockTag return false if no block ref foundwalformat5

4 files changed, 10 insertions, 19 deletions

diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 0514ba1c4a..8d587eab58 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -7628,11 +7628,10 @@ heap_xlog_update(XLogRecPtr lsn, XLogRecord *record, bool hot_update)
 	oldtup.t_len = 0;
 
 	XLogRecGetBlockTag(record, 0, &rnode, NULL, &newblk);
-	if (XLogRecHasBlockRef(record, 1))
+	if (XLogRecGetBlockTag(record, 1, NULL, NULL, &oldblk))
 	{
 		/* HOT updates are never done across pages */
 		Assert(!hot_update);
-		XLogRecGetBlockTag(record, 1, NULL, NULL, &oldblk);
 	}
 	else
 		oldblk = newblk;
diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c
index 1dd909b2fa..4ada69360d 100644
--- a/src/backend/access/nbtree/nbtxlog.c
+++ b/src/backend/access/nbtree/nbtxlog.c
@@ -208,9 +208,7 @@ btree_xlog_split(bool onleft, bool isroot,
 
 	XLogRecGetBlockTag(record, 0, NULL, NULL, &leftsib);
 	XLogRecGetBlockTag(record, 1, NULL, NULL, &rightsib);
-	if (XLogRecHasBlockRef(record, 2))
-		XLogRecGetBlockTag(record, 2, NULL, NULL, &rnext);
-	else
+	if (!XLogRecGetBlockTag(record, 2, NULL, NULL, &rnext))
 		rnext = P_NONE;
 
 	/*
diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c
index 64876f7998..d3ff06e74c 100644
--- a/src/backend/access/transam/xlogreader.c
+++ b/src/backend/access/transam/xlogreader.c
@@ -1076,8 +1076,12 @@ XLogRecHasBlockImage(XLogRecord *record, uint8 block_id)
 
 /*
  * Returns information about the block that a block reference refers to.
+ *
+ * If the WAL record contains a block reference with the given ID, *rnode,
+ * *forknum, and *blknum are filled in (if not NULL), and returns TRUE.
+ * Otherwise returns FALSE.
  */
-void
+bool
 XLogRecGetBlockTag(XLogRecord *record, uint8 block_id,
 				   RelFileNode *rnode, ForkNumber *forknum, BlockNumber *blknum)
 {
@@ -1085,18 +1089,7 @@ XLogRecGetBlockTag(XLogRecord *record, uint8 block_id,
 
 	bkpb = XLogRecGetBlockRef(record, block_id, NULL);
 	if (bkpb == NULL)
-	{
-#ifdef FRONTEND
-		if (rnode)
-			rnode->spcNode = rnode->dbNode = rnode->relNode = InvalidOid;
-		if (forknum)
-			*forknum = InvalidForkNumber;
-		if (blknum)
-			*blknum = InvalidBlockNumber;
-#else
-		elog(ERROR, "failed to locate backup block with ID %d", block_id);
-#endif
-	}
+		return false;
 	else
 	{
 		if (rnode)
@@ -1105,6 +1098,7 @@ XLogRecGetBlockTag(XLogRecord *record, uint8 block_id,
 			*forknum = bkpb->fork_flags & BKPBLOCK_FORK_MASK;
 		if (blknum)
 			*blknum = bkpb->block;
+		return true;
 	}
 }
 
diff --git a/src/include/access/xlogrecord.h b/src/include/access/xlogrecord.h
index ba00b4eaba..35ef7e5754 100644
--- a/src/include/access/xlogrecord.h
+++ b/src/include/access/xlogrecord.h
@@ -157,7 +157,7 @@ extern bool XLogRecHasBlockRef(XLogRecord *record, uint8 block_id);
 extern bool XLogRecHasBlockImage(XLogRecord *record, uint8 block_id);
 extern uint8 *XLogRecGetBlockRefIds(XLogRecord *record, int *num_refs);
 extern char *XLogRecGetBlockData(XLogRecord *record, uint8 block_id, Size *len);
-extern void XLogRecGetBlockTag(XLogRecord *record, uint8 block_id,
+extern bool XLogRecGetBlockTag(XLogRecord *record, uint8 block_id,
 				 RelFileNode *rnode, ForkNumber *forknum,
 				 BlockNumber *blknum);